Safety cap

ABSTRACT

A safety bottle cap that cannot be opened by inquisitive children yet is readily openable by adults comprises a hollow member with a hollow portion large enough to encompass a screw thread disposed about a container, said hollow member comprising an upper portion separated from a lower portion by a central portion, said central portion being comprised of flexible material so that said bottom portion may be moved relative to said top portion by flexing said flexible material, said hollow member further comprising a locking member having a width less than the distance between adjacent flights of said screw thread, said locking member including a locking surface, said locking surface having a complementary shape with respect to the terminal end surface of said screw thread in order to permit said locking surface to mate with said end surface of said screw thread, said central portion having an unflexed height less than the distance between the top of said container and said terminal end surface of said screw thread to permit said locking surface to mate with the end surface of said screw thread only when said flexible central portion is in at least a partially flexed position whereby the tendency of said central portion to return to its unflexed condition exerts an upward bias on said locking member.

United States Patent [72] lnventor Millard C. Fitzgerald 25 Yarmouth Lane, Media, Pa. 19063 [21 Appl. No. 6,803

[22] Filed Jan. 29, 1970 [45] Patented Sept. 28, 1971 [54] SAFETY CAP 23 Claims, 19 Drawing Figs.

Primary Examiner-George T. Hall Attorney-Shaffert and Miller 1 swarm ABSTRACT: A safety bottle cap that cannot be opened by inquisitive children yet is readily openable by adults comprises a hollow member with a hollow portion large enough to encompass a screw thread disposed about a container, said hollow member comprising an upper portion separated from a lower portion by a central portion, said central portion being comprised of flexible material so that said bottom portion may be moved relative to said top portion by flexing said flexible material, said hollow member further comprising a locking member having a width less than the distance between adjacent flights of said screw thread, said locking member including a locking surface, said locking surface having a complementary shape with respect to the terminal end surface of said screw thread in order to permit said locking surface to mate with said end surface of said screw thread, said central portion having an unflexed height less than the distance between the top of said container and said terminal end surface of said screw thread to permit said locking surface to mate with the end surface of said screw thread only when said flexible central portion is in at least a partially flexed position whereby the tendency of said central portion to return to its unflexed condition exerts an upward bias on said locking member.

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SHEET 1 OF 3 v INVEN'IOR MILLARD C; FITZGERALD PAT-ENTEU SEP28 I9?! SHEET 2 0F 3 mv ENTOII MILLARD C. FITZGERALD PATENTEIJSEP28|971 I 73608-162 sum 3 OF 3 mvl-zn'mn MILLARD C. FITZGERALD SAFETY CAP The fascination of small children with containers of medicine is an all too well-known occurrence. Commonly known containers of medicine have caps that may be very easily opened by children, often to their detriment.

Recognition of this problem has led to a considerable number of various safety caps which are intended to baffle the attempts of children to open them. However, these attempts to produce a commercially successful safety cap that cannot be opened by children have not met with considerable success.

In order to be commercially successful, a safety cap must meet a number of requirements. Firstly, the safety cap must be relatively easy for adults to use. Thus, the locking and unlocking of the cap before and after legitimate adult use must be easily accomplished with a minimum effort. At the same time though, this minimum effort must be of such a nature that a child will not readily learn the manner of operation of such a cap by either observation or experimentation.

Economic considerations play a large part in the commercial acceptability of such a safety cap. Thus, to be commercially acceptable, a safety cap must not substantially add to the cost of the package consisting of the contents and the closeable container. Therefore, the safety cap must be comprised of a simple structure involving only a minimum of extra parts. In addition, the safety cap should be compatible with existing container construction, i.e. the cap itself should contain all necessary components of the locking mechanism.

Accordingly, it is an object of the present invention to provide a safety cap that cannot be opened by children yet is readily openable by adults.

It is another object of the present invention to provide a safety cap that is of a simple inexpensive construction.

It is a further object of the present invention to provide a safety cap that is compatible with existing container construction.

Other objects will appear hereinafter.

In accordance with the present invention, a safety cap is provided that is compatible with the conventional. medicinal container having a cylindrical neck with a male screw thread.

The safety cap of the instant invention is comprised of a top cylindrical portion connected to a bottom cylindrical skirt portion by a flexible central portion. This flexible portion allows axial movement of the skirt relative to the cap top.

A locking tab is located on the inside of the skirt portion and is so dimensioned as to be engageable between adjacent flights of the screw thrcad disposed about the neck of the container.

As the cap is screwed onto the container, the locking tab moves progressively downward between the flights of the screw thread. As the locking tab moves downwardly, the cap top which is restrained against the top of the neck of the container remains stationary. This causes the central flexible portion of the cap to expand or flex thereby allowing the skirt portion to be axially displaced with respect to the cap top. This expansion of the central flexible portion results in the application of an upward bias to the skirt portion which upward bias is transmitted to the locking tab. The locking tab continues its downward motion as the cap is rotated until the locking tab reaches the end of the screw thread. At this point, the locking tab, which is preferably L-shaped, engages the terminal end surface of the screw thread because of the previously mentioned upward biasing force. Thus, the locking tab lockably engages the terminal end surface of the screw thread of the container.

Due to this manner of locking, the safety cap of the present invention cannot be removed by merely reversing the direction of rotation. Thus, to remove the cap, it is necessary to pull the skirt axially downward along the container neck until the locking tab is disengaged from the terminal end surface of the screw thread. After the locking tab is so disengaged, the capof the present invention may be removed from the container by merely applying a rotational force in the unlocking direction. I

In another embodiment of the present invention, the safety cap is provided with an interior tab seal which produces a tighter fit between the safety cap top and the neck of the container. This tab seal is formed as an integral portion of the safety cap and is forced into contact with the lip of the container as the flexible portion of the cap is expanded or flexed. Maximum sealing force is achieved when the locking tab is engaged with the terminal end surface of the screwthread.

In a further embodiment of the present invention, the safety cap is provided with both an internal tab seal and an external tab seal to provide an even tighter fit between the safety cap top and the lip of the container to be sealed.

For the purpose of illustrating the invention, there is shown in the drawings forms which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.

FIG. 1 is a perspective view of a first embodiment of the present invention showing the cap top, skirt, and a flexible central portion formed from flexible segmented arms.

FIG. 2 is a perspective view of a second embodiment of the present invention wherein the flexible central portion of the safety cap is comprised of a horizontal expansion bellows.

FIG. 3 is a perspective view of a third embodiment of the present invention wherein the flexible portion of the safety cap is comprised of a vertical expansion bellows.

FIG. 4 is a perspective view of the locking tab of the present invention shown disposed on the interior surface of the skirt portion of the safety cap.

FIG. 5 is a split sectional view of the embodiment shown in FIG. I with the safety cap of the present invention shown in the unlocked position.

FIG. 6 is a split sectional view of the embodiment shown in FIG. 1 with the safety cap of the present invention shown in the locked position.

FIG. 7 is a split sectional view of the embodiment shown in FIG. 2 with the safety cap of the present invention shown in the unlocked position.

FIG. 8 is a split sectional view of the embodiment shown in FIG. 2 with the safety cap of the present invention shown in the locked position.

FIG. 9 is a split sectional view of the embodiment shown in FIG. 3 with the safety cap of the present invention shown in the unlocked position.

FIG. 10 is a split sectional view of the embodiment shown in FIG. 3 with'the safety capof the present invention shown in the locked position.

FIG. 11 is an elevation view of the neck of the container with the locking tab shown in section between two adjacent flights of the screw thread.

FIG. 12 is an elevation view of the neck of the container showing he locking tab in locking engagement with the terminal end surface of the screw thread.

FIG. 13 is an elevational view of the neck of a container with two separate screw threads with the hidden portions of each thread shown in dotted lines.

FIG. 14 is a split sectional view of the embodiment shown in FIG. I wherein the safety cap of the present invention is provided with internal and external tab seals. FIG. 14 shows these tab seals in the unlocked position.

FIG. 15 is a view of the safety cap of FIG. 14 showing the internal and external tab seals in the locked position.

FIG. 16 is a split sectional view of the embodiment shown in FIG. Z'Wherein the safety cap of the present invention is provided with an internal tab seal. FIG. 16 shows the tab seal in the unlocked position.

FIG. 17 is a view of the safety cap of FIG. 16 showing the tab seal in the locked position.

FIG. 18 is a split sectional view of the embodiment shown in FIG. 3 wherein the safety cap of the present invention is provided with an internal tab seal. FIG. 18 shows the tab seal in the unlocked position.

FIG. 19 is a viewof the safety cap of FIG. 18 showing the tab seal in the locked position.

Referring to the drawings in particular wherein like numerals designate like elements there is shown in FIG. 1 a first embodiment of the present invention. The safety cap in FIG. 1, generally designated as 10, is comprised of cap top 12 which is joined to skirt 24 by flexible slats 20. In particular, top 12 is joined to flexible slats 20 by upper hinge 14. Similarly, flexible slats 20 are joined to skirt 24 by lower hinge 22.

As shown in FIG. 1, slats 20 are separated from each other by slots 16. Each slat 20 has a groove 18 formed therein which acts as a middle hinge. Thus, as skirt 24 is axially displaced with respect to top I2, the segmented portions of each slat 20 are angularly displaced about groove 18 which functions as a middle hinge.

A second embodiment of the safety cap of the present invention is shown in FIG. 2 and is generally designated as 30. Safety cap 30 is comprised of top 32 joined to skirt 38 by horizontal expansion bellows 34. As shown in FIG. 2, horizontal expansion bellows 34 is comprised of a plurality of concentric horizontally displaced flutes 36.

A third embodiment of the safety cap of the present invention is shown in FIG. 3 and is generally designated as 40. Safety cap 40 is comprised of top 42 which is connected to skirt 48 by vertical expansion bellows 44. As shown in FIG. 3, vertical expansion bellows 44 is comprised of a plurality of concentric vertically disposed flutes 46.

FIG. 4 shows locking tab 50 disposed along the interior surface of skirt 24. As shown in FIG. 4, locking tab 50 is comprised of detent surface 54, upper surface 52 and lower surface 56. Although not shown, locking tab 50 is similarly disposed with respect to skirts 38 and 48 of FIGS. 2 and 3, respectively.

FIG. shows the safety cap of FIG. I in the unlocked position. As shown in FIG. 5, neck 58 of the container to be closed has screw thread 62 disposed therearound. Locking tab 50 is shown disposed between adjacent flights of screw thread 62. Disc seal 64 is provided on the underside of top 12 in order to provide a tight closure between safety cap and lip 60 of neck 58.

FIG. 6 shows the safety cap of FIG. 5 in the locked position. As is readily apparent from FIG. 6, the angular separation between the segmented parts of slats has been greatly increased. As mentioned above, this expansion or flexing of slats 20 causes an upward bias to be applied to locking tab 50.

FIG. 7 shows the safety cap of FIG. 2 in the unlocked position. Disc seal 66 is provided on the underside of top 32 in order to effect a tight closure between safety cap 30 and lip 72 of neck 70. As shown in FIG. 7, screw thread 68 is disposed about neck 70 and locking tab 50 is disposed between adjacent flights of screw thread 68. In the unlocked position, flutes 36 of horizontal expansion bellows 34 are concentrically and horizontally disposed with respect to the center of neck 70.

FIG. 8 shows the safety cap of FIG. 7 in the locked position. As mentioned above, the displacement of flutes 36 from the position shown in FIG. 7 to the position illustrated in FIG. 8 creates the application of an upward bias to locking tab 50.

FIG. 9 shows the safety cap of FIG. 3 in the unlocked position. Screw thread 78 is disposed about neck 74. A disc seal 80 is disposed on the underside of top 42 in order to effect a tight closure between lip 76 of neck 74 and safety cap 40. As shown in FIG. 9, flutes 46 of the vertical expansion bellows are closely spaced with respect to each other. Locking tab 50 is disposed between adjacent flights of screw thread 78.

FIG. 10 shows the safety cap of FIG. 9 in the locked position. As is readily apparent from FIG. 10, the movement of locking tab 50 along screw thread 78 causes the displacement of flutes 46 with respect to each other. As mentioned above, this causes an upward bias to be exerted on locking tab 50.

FIG. 11 shows the disposition of locking tab 50 between adjacent flights of screw thread 62. The end surface of screw thread 62 is designated as 82 in FIG. 11. Locking tab 50 is so dimensioned so as to be capable of movement between ad jacent flights of screw thread 62. As shown in FIG. Ill, upper surface 52 and lower surface 56 of locking tab 50 guide locking tab 50 as it travels downwardly between the flights of screw thread 62. The arrow in FIG. 1 I indicates this direction of travel.

FIG. 12 shows locking tab 50 in locked engagement with end surface 82 of screw thread 62. As noted above, the extension of the flexible central portion of the safety cap causes an upward force to be applied to locking tab 50. Therefore, when locking tab 50 reaches the end of screw thread 62, the L- shaped locking tab 50 is upwardly displaced. This causes detent surface 54 of the locking tab 50 to be brought into en gagement with thread end surface 82. Due to the position of detent surface 54, it is readily apparent from FIG. 12 that the safety cap cannot be removed by merely applying a rotational force in the unlocking direction. In order to remove the safety cap from neck 58, it is first necessary to further displace the flexible central portion of the safety cap in order to cause locking tab 50 to be downwardly displaced. This allows upper surface 52 of locking tab 50 to make contact with the bottom of screw thread 62. Once in this position, the application of a rotational force in the unlocking direction for a predetermined period is sufficient to remove the safety cap from neck 58.

FIG. 13 shows a neck 58 provided with dual screw threads 84 and 86 whichare displaced from each other by 180. A safety cap of the present invention having two locking tabs 50 could be utilized with such a container. With such an arrangement, one locking tab would mate with screw thread 84 while the other locking tab would mate with screw thread 86.

FIG. 14 shows the embodiment of FIG. 1 in the unlocked position wherein the safety cap is provided with an internal and an external tab seal in order to provide a tighter fit between the safety cap and the lip of the container to be closed. As shown in FIG. 14, groove 90 is provided in top 12 in order to permit slat 20 to rotate about top 12. Thus, groove 90 functions as a hinge member. Tab seals 88 are provided on op posite sides of groove 90. As the angular displacement between the segmented parts of slots 20 is increased (see FIGS. 5 and 6), tab seals 88 form a tight seal against the interior and exterior of lip 60.

FIG. 15 shows the safety cap of FIG. 14, and in particular tab seals 88, in the locked position. Because tab seals 88 form such a tight fit with lip 60 of neck 58, there is not need to provide a disc seal 64 on the under side of top 12 such as is shown in FIGS. 5 and 6.

FIG. 16 shows the embodiment of FIG. 2 wherein the safety cap is provided with an internal tab seal in order to effect a tighter fit between he safety cap and the lip of the container to be closed. FIG. 16 shows the safety cap in the unlocked position. As shown in the Figure, innermost flute 36 is separated from top 32 by groove 92. Groove 92 functions as a hinge member allowing flutes 36 to rotate about top 32. Internal tab seal 94 is provided on the underside of top 32.

FIG. 17 shows the safety cap of FIG. 16 is the locked position. As shown in FIG. 17, the extension of flexible flutes 36 causes a tight seal to be formed about lip 72 of neck 70. This closure is so effective that there is no need to provide a disc seal 66 on the underside of top 32 such as is shown in FIGS. 7 and 8.

FIG. 18 shows the embodiment of FIG. 3 wherein the safety cap is provided with an internal tab seal in order to effect a tighter fit between the safety cap and the lip of the container to be closed. FIG. 18 shows the safety cap in the unlocked position. As shown in the Figure, topmost flute 46 is separated from top 42 by groove 96. Because of its placement, groove 96 acts as a hinge member permitting rotation of flutes 46 about top 42. Internal tab seal 98 is provided on the underside of top 42 in order to effect tight fit between the safety cap and lip 76.

FIG. 19 shows the safety cap of FIG. 18 in the locked position. As flute 46 is displaced downwardly, flute 46 is brought into tighter engagement with lip 76 of neck 74. This downward displacement also causes internal tab seal 98 to form a tighter fit with lip 76. Because of the tight fit formed between flute 46 and internal tab seal 98 with lip 76, there is no necessity to provide a disc seal 80 on the underside of top 42 such as is shown in FIGS. 9 and 10.

The present invention may be embodied in other specific forms without departing from the spirit or central attributes thereof. For example, it is not necessary that locking tab 50 have a width equal to the distance between adjacent thread flights. It is sufficient if the width is any width smaller than the distance between adjacent thread flights. Although it is desirable to contain the entire locking mechanism within the cap, it would be relatively easy to provide the neck of the container to be closed with the locking tab and to provide the cap with the male screw thread. Accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

lclaim:

l. The combination of a container and a safety cap comprising:

A. a container,

B. screw thread means disposed exteriorly about one end of said container, said screw thread means having an end surface; and

C. a hollow safety cap of sufficient size to encompass said screw thread means comprising l. an upper portion having an interior surface adapted to abut the extremity of said one end of said container,

2. a lower portion,

3. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, and

4. locking means a. having a width less than the distance between adjacent flights of said screw thread means and b. including a locking surface of a shape complementary to said end surface to mate with said end surface,

D. said locking means being spaced from said interior surface of said upper portion, when said central portion is unflexed, a distance less than the distance between said end surface of said screw thread means and said extremity of said one end of said container,

E. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.

2. The combination of claim 1 wherein said locking means is L-shaped.

3. The combination of claim 1 wherein said flexible central portion is comprised of a plurality of slats separated from each other by a plurality of slots.

4. The combination of claim 1 wherein said flexible central portion is comprised of a horizontal expansion bellows comprising a plurality of horizontally disposed flutes.

5. The combination of claim 1 wherein said flexible central portion is comprised of a vertical expansion bellows comprising a plurality of vertically disposed flutes.

6. The combination of claim 3 wherein said upper portion is hinged to one end of said slats, said lower portion is hinged to the other end of said slats, and wherein said slats have a reduced portion intermediate the ends thereof.

7. The combination of elaiml' wherein said upper portion includes a disc seal.

8. The combination of claim 1 wherein said screw thread means comprises two screw threads, each of said screw threads having an end surface, and wherein said locking means comprises two locking members, each of said locking members having a locking surface capable of mating with one of said end surfaces of one of said screw threads.

9. The combination of claim 3 wherein said hollow safety cap comprises an internal tab seal and an external tab seal cooperating to sealingly engage said extremity of said one end of said container.

10. The combination of claim 4 wherein said hollow safety cap comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.

11. The combination of claim 5 wherein said hollow safety cap comprises an internal tab seal cooperating with said bcl' lows to sealingly engage said extremity of said one end of said container.

12. A hollow safety cap of sufficient size to encompass screw thread means having an end surface disposed about one end of a container comprising:

A. an upper portion having an interior surface adopted to abut the extremity of said one end of said container, B. a lower portion, C. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, and D. locking means 1. having a width less than the distance between adjacent flights of said screw thread means and 2. including a locking surface of a shape complementary to the shape of said end surface of said screw thread means to permit said locking surface to mate with said end surface,

E. said locking means being spaced from said interior surface of said upper portion, when said central portion is unflexed, a distance less than the distance between said end surface of said screw thread means and said extremity of said one end of said container,

F. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.

13. The safety cap of claim 12 wherein said locking means is L-shaped.

14. The safety cap of claim 12 wherein said flexible central portion is comprised of a plurality of slats separated from each other by a plurality of slots.

15. The safety can of claim 12 wherein said flexible central portion is comprised of a horizontal expansion bellows comprising plurality of horizontally disposed flutes.

16. The safety cap of claim 12 wherein said flexible central portion is comprised of a vertical expansion bellows comprising a plurality of vertically disposed flutes.

17. The safety cap of claim 14 wherein said upper portion is hinged to one end of said slats, said lower portion is hinged to the other end of said slats, and wherein said slats have a reduced portion intermediate the ends thereof.

18. The safety cap of claim 12 wherein said upper portion includes a disc seal.

19. The safety cap of claim 12 wherein said locking means comprises two locking members.

20. The safety cap of claim 14 wherein said upper portion comprises an internal tab seal and an external tab seal cooperating to sealingly engage said extremity of said one end of said container.

21. The safety cap of claim 15 wherein said upper portion comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.

22. The safety cap of claim 16 wherein said upper portion comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.

23. The combination of a container and safety cap comprising:

A. a container,

B. screw thread means having an end surface,

C. a hollow safety cap comprising 1. an upper portion having an interior surface adapted to abut the extremity of said container, 2. a lower portion,

F. said locking mans being mounted to the other of said container of said safety cap,

G. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means. 

1. The combination of a container and a safety cap comprising: A. a container, B. screw thread means disposed exteriorly about one end of said container, said screw thread means having an end surface; and C. a hollow safety cap of sufficient size to encompass said screw thread means comprising
 1. an upper portion having an interior surface adapted to abut the extremity of said one end of said container,
 2. a lower portion,
 3. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, and
 4. locking means a. having a width less than the distance between adjacent flighTs of said screw thread means and b. including a locking surface of a shape complementary to said end surface to mate with said end surface, D. said locking means being spaced from said interior surface of said upper portion, when said central portion is unflexed, a distance less than the distance between said end surface of said screw thread means and said extremity of said one end of said container, E. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.
 2. a lower portion,
 2. The combination of claim 1 wherein said locking means is L-shaped.
 2. including a locking surface of a shape complementary to the shape of said end surface of said screw thread means to permit said locking surface to mate with said end surface, E. said locking means being spaced from said interior surface of said upper portion, when said central portion is unflexed, a distance less than the distance between said end surface of said screw thread means and said extremity of said one end of said container, F. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.
 2. a lower portion,
 3. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, D. locking means including a locking surface of a shape complementary to said end surface to permit said locking surface to mate with said end surface, E. Said screw thread means being mounted to one of either said container or said safety cap, F. said locking means being mounted to the other of said container or said safety cap, G. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.
 3. The combination of claim 1 wherein said flexible central portion is comprised of a plurality of slats separated from each other by a plurality of slots.
 3. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, and
 4. locking means a. having a width less than the distance between adjacent flighTs of said screw thread means and b. including a locking surface of a shape complementary to said end surface to mate with said end surface, D. said locking means being spaced from said interior surface of said upper portion, when said central portion is unflexed, a distance less than the distance between said end surface of said screw thread means and said extremity of said one end of said container, E. whereby said central portion is at least partially flexed when said locking surface mates with said end surface and the tendency of said central portion to return to its unflexed position exerts a bias on said locking means.
 4. The combination of claim 1 wherein said flexible central portion is comprised of a horizontal expansion bellows comprising a plurality of horizontally disposed flutes.
 5. The combination of claim 1 wherein said flexible central portion is comprised of a vertical expansion bellows comprising a plurality of vertically disposed flutes.
 6. The combination of claim 3 wherein said upper portion is hinged to one end of said slats, said lower portion is hinged to the other end of said slats, and wherein said slats have a reduced portion intermediate the ends thereof.
 7. The combination of claim 1 wherein said upper portion includes a disc seal.
 8. The combination of claim 1 wherein said screw thread means comprises two screw threads, each of said screw threads having an end surface, and wherein said locking means comprises two locking members, each of said locking members having a locking surface capable of mating with one of said end surfaces of one of said screw threads.
 9. The combination of claim 3 wherein said hollow safety cap comprises an internal tab seal and an external tab seal cooperating to sealingly engage said extremity of said one end of said container.
 10. The combination of claim 4 wherein said hollow safety cap comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.
 11. The combination of claim 5 wherein said hollow safety cap comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.
 12. A hollow safety cap of sufficient size to encompass screw thread means having an end surface disposed about one end of a container comprising: A. an upper portion having an interior surface adopted to abut the extremity of said one end of said container, B. a lower portion, C. a flexible central portion joining said lower portion to said upper portion to permit relative motion between said lower and upper portions, and D. locking means
 13. The safety cap of claim 12 wherein said locking means is L-shaped.
 14. The safety cap of claim 12 wherein said flexible central portion is comprised of a plurality of slats separated from each other by a plurality of slots.
 15. The safety cap of claim 12 wherein said fleXible central portion is comprised of a horizontal expansion bellows comprising plurality of horizontally disposed flutes.
 16. The safety cap of claim 12 wherein said flexible central portion is comprised of a vertical expansion bellows comprising a plurality of vertically disposed flutes.
 17. The safety cap of claim 14 wherein said upper portion is hinged to one end of said slats, said lower portion is hinged to the other end of said slats, and wherein said slats have a reduced portion intermediate the ends thereof.
 18. The safety cap of claim 12 wherein said upper portion includes a disc seal.
 19. The safety cap of claim 12 wherein said locking means comprises two locking members.
 20. The safety cap of claim 14 wherein said upper portion comprises an internal tab seal and an external tab seal cooperating to sealingly engage said extremity of said one end of said container.
 21. The safety cap of claim 15 wherein said upper portion comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.
 22. The safety cap of claim 16 wherein said upper portion comprises an internal tab seal cooperating with said bellows to sealingly engage said extremity of said one end of said container.
 23. The combination of a container and safety cap comprising: A. a container, B. screw thread means having an end surface, C. a hollow safety cap comprising 